Tamper-evident package

ABSTRACT

An improved tamper-evident package includes a plastic closure having a top wall portion, a depending annular skirt portion, and a tamper band at least partially detachably connected to the skirt portion. The package includes a container having a neck portion configured for tamper-indicating cooperation with the projections on the tamper band. The container includes a plurality of circumferentially spaced ratchet-like locking teeth, each of which presents a locking surface for interfering engagement with the respective one of the projections on the closure tamper band. Notably, disposition of the flexible projections of the pilfer band in pre-determined relationship to an internal thread formation of the closure permits the flexible projections to be positioned so that each of the locking teeth on the container is engaged by a respective one of the flexible projections attendant to very little relative rotation of the closure relative to the container during removal.

TECHNICAL FIELD

The present invention relates generally to tamper-evident packaging forproducts, and more particularly to a tamper-evident package comprising acontainer and cooperating closure which are configured for efficientmanufacture, and which functions to provide readily visually discernableevidence of opening attendant to very limited opening movement of theclosure of the package.

BACKGROUND OF THE INVENTION

Tamper-evident packaging is in very widespread use by virtue of theassurance it provides consumers that the contents of the package arefresh and unadulterated. While it is known to provide packages withtamper-evident overwraps, heat-shrinkable films, and the like, sucharrangements can complicate high-speed processing, and undesirably addto the cost of packaging.

In view of this, packaging arrangements have been developed,particularly closures for containers, which include a tamper-evidentfeature as part of the closure structure. By way of example, U.S. Pat.No. 4,418,828, No. 4,497,765, and No. 5,205,426, all hereby incorporatedby reference, illustrate tamper-evident plastic closure constructionswhich have met with widespread acceptance in the marketplace by virtueof their reliable function and economical manufacture.

For some packaging applications, it is desirable to provide a containerclosure having a so-called “multi-start” thread formation, whichincludes plural helical thread elements which cooperate with likeelements on the container to effect closure retention and sealing. Sucharrangements permit closure application and removal with relativelylittle rotation of the closure with respect to the associated container.

For such applications, it is necessary that any tamper-indicatingarrangement function attendant to very little relative rotation of aclosure with respect to the associated container, since complete closureremoval is effected by little relative rotation. To this end, U.S. Pat.No. 6,557,714, hereby incorporated by reference, discloses atamper-evident package including a container and closure havingcooperating multi-start thread formations, with the tamper-evidentarrangement of the package functioning to provide tamper-indication,typically attendant to no more than about 15° of rotation of the closureduring removal.

In this previous construction, tamper-indication for the package isachieved by the provision of a plurality of ratchet-like locking teethon the package container, with the associated closure including a tamperband having a plurality of flexible projections configured forcooperative engagement with the container locking teeth. In order toassure rapid tamper-indication during closure removal, the flexibleprojections of the closure tamper band are closely spaced together. Inthe event that one or more of the flexible projections is not positionedfor locking engagement with a respective container locking tooth afterclosure application, very limited relative rotation is required duringclosure removal to present a successive one of the flexible projectionsfor locking engagement with the container locking tooth.

The present invention is directed to an improved form of thetamper-evident package of the above-referenced U.S. Pat. No. 6,557,714,wherein tamper-indication is provided attendant to very little relativerotation of the package closure, preferably prior to unsealing of thecontainer by the closure during removal.

SUMMARY OF THE INVENTION

A tamper-indicating package embodying the principles of the presentinvention includes a cooperating plastic closure and container, whereinthe container has been particularly configured to providetamper-indicating cooperation with the closure. The closure includes atamper band having a plurality of circumferentially spaced, inwardlyextending flexible projections which cooperate with a plurality ofcircumferentially spaced, ratchet-like locking teeth on the container toprovide tamper-indication during opening of the package.

Notably, the flexible projections of the closure are positioned in apre-determined relationship to the associated closure thread formation,with the flexible projections sufficiently spaced apart to permit atleast one of the container locking teeth to be positioned betweenadjacent ones of the flexible projections when the closure is fullyapplied to the container. By this arrangement, preferably each one ofthe container locking teeth is engaged by a respective one of theflexible projections during closure removal, attendant to as little as5° of relative rotation, or less, thereby desirably providing very rapidtamper-indication during closure removal. Such rapid tamper-indicationcan desirably be provided prior to unsealing of the container duringclosure removal, even when the package includes multi-start threadformations which permit complete closure removal with very littlerelative rotation.

In accordance with the illustrated embodiment, the container of thepresent tamper-evident package has a neck portion defining an opening,with the container having an external thread formation on the neckportion. The thread formation includes at least one helical threadelement, with the presently preferred configuration comprising aplurality of thread elements, sometimes referred to as “multi-start”threads, to permit the package to be opened by very little relativerotation of the associated closure. It is within the purview of thepresent invention that other closure retention arrangements can beemployed, such as cooperating single-thread formations, or cooperatinglug-type thread elements on the container and associated closure.

In accordance with the illustrated embodiment, the container of thepackage includes a plurality of circumferentially spaced locking teethpositioned on the neck portion of the container beneath the threadformation. Each of the locking teeth has a generally ratchet tooth-likeconfiguration, and includes a locking surface, and a generally outwardlytapering guide surface, opposite the locking surface, extending from theneck portion generally toward the locking surface. In the preferredembodiment, the locking surface of each locking tooth is generallyradially and vertically oriented.

Notably, the locking teeth are unevenly spaced about the neck portion ofthe container, with the spacing corresponding to the spacing between theflexible projections on the closure pilfer band, or multiples thereof.In accordance with the illustrated embodiment, the locking teeth areprovided in first and second groups positioned in diametrically opposedrelationship on the neck portion of the container, with the lockingteeth of each of the groups evenly circumferentially spaced apart. Tofacilitate locking cooperation with the flexible projections of theassociated closure, the container includes an annular shoulderpositioned adjacent to and above the locking teeth, and beneath theexternal thread formation on the container. The locking teeth are atleast partially positioned beneath the annular shoulder, and preferablyare positioned substantially completely beneath the annular shoulder.

The closure of the present tamper-evident package is configured forfitment to the neck portion of the container for closing the openingtherein. The closure include a top wall portion, and a depending annularskirt portion having an internal thread formation for mating engagementwith the external thread formation on the neck portion of the container.Again, the closure preferably includes a multi-start thread formation,including plural helical thread elements, to promote convenient andefficient application and removal of the closure.

The closure of the present package is configured for tamper-indicatingcooperation with the container by the provision of a tamper banddepending from and at least partially detachably connected to the skirtportion of the closure by a frangible connection. As desired, the pilferband may be configured for complete detachment from the skirt portion ofthe closure, or partial detachment, whereby the tamper band remainsjoined to the skirt portion attendant to closure removal.

The tamper band of the closure includes an annular band portion, and aplurality of inwardly extending flexible projections, each movable abouta respective hinge portion joined to the annular band portion. In thepreferred form, the hinge portion of each projection is relatively thin,thus promoting high-speed application of the closure to the containerwith minimal resistance from the tamper band, while still permitting theflexible projections to be configured to exhibit the desired rigidityfor lockingly engaging the container locking teeth, and fracturing thefrangible connection between the pilfer band and the closure skirt.

At least one of the projections of the tamper band is engageable with atleast one of the locking teeth on the container, during removal of theclosure from the container, for fracturing the frangible connection toprovide visual evidence of opening of the package. Notably, the flexibleprojections of the tamper band are positioned in predeterminedcircumferential relationship with respect to the internal threadformation of the closure. By such an arrangement, the position of theflexible projections, relative to the container locking teeth when theclosure is fully applied, can be very effectively predetermined. As aconsequence, the present package permits each one of the containerlocking teeth to be engaged by a respective one of the flexibleprojections during closure removal, thus permitting very rapidtamper-indication during closure removal. To effect such one-to-onelocking engagement, the flexible projections are spaced apart by adistance at least as great as the circumferential dimension of each ofthe locking teeth, that is, the flexible projections arecircumferentially spaced sufficiently so as to receive one of thecontainer locking teeth between adjacent ones of the flexibleprojections when the closure is fully applied to the container.

In order to promote closely fitting relationship between the containerlocking teeth and the flexible projections of the closure for rapidtamper-indication during removal, the flexible projections of theclosure are preferably inwardly tapering.

Other features and advantages of the present invention will becomereadily apparent from the following detailed description, theaccompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, respective view of a tamper-evident packageembodying the principles of the present invention, including acooperating plastic closure and associated container:

FIG. 2 is a cross-sectional view of the closure of the present packageillustrated in FIG. 1;

FIG. 3 is a fragmentary, side elevational view of a neck portion of thecontainer of the present package illustrated in FIG. 1;

FIG. 4 is a plan view of the interior of the closure of the presentpackage illustrated in FIG. 1;

FIG. 5 is a cross-sectional view of the neck portion of the container ofthe present package, taken along lines 5-5 of FIG. 3; and

FIG. 6 is a diagrammatic view illustrating the present package, and thecooperative fitment of the closure and container of the package.

DETAILED DESCRIPTION

While the present invention is susceptible of embodiment in variousforms, there is shown in the drawings, and will hereinafter bedescribed, a presently preferred embodiment, with the understanding thatthe present disclosure is to be considered as an exemplification of theinvention, and is not intended to limit the invention to the specificembodiment illustrated.

With reference to FIG. 1, therein is illustrated a tamper-evidentpackage 10 embodying the principles of the present invention. As will befurther described, package 10 includes a cooperating closure 12 andcontainer 14 (partially illustrated in phantom line) which can beconfigured for economical use for beverages or like contents. It can beparticularly desirable to configure the package 12 for convenientopening and removal of closure 12, with relatively little rotation ofthe closure relative to the container 14 when it is desired to provide atamper-evident function prior to unsealing of the associated container.Thus, as will be further described, the tamper-evident feature of thepresent package is particularly configured to promote tamper-indicationattendant to very little rotation of the closure relative to thecontainer.

With particular reference to FIGS. 2 and 4, therein is illustratedclosure 12 of the present tamper-evident package. Closure 12 ispreferably molded from suitable polymeric material (typicallypolypropylene), and may be efficiently injection-molded, orcompression-molded, such as in accordance with the teachings of U.S.Pat. No. 4,497,765, hereby incorporated by reference.

As illustrated, closure 12 includes a circular top wall portion 16, anda depending annular skirt portion 18. Skirt portion 18 includes aninternal thread formation which, in the preferred form, comprises aplurality of generally helical thread elements 20, with the threadformation thus configured as a so-called multi-start thread. Thisarrangement facilitates application and removal of the closure to andfrom the associated container with a relatively small degree of rotationof the closure relative to the container.

To provide the desired sealing cooperation between the closure 12 andcontainer 14, the closure includes a generally disc-shaped sealing liner22 positioned on the inside surface of the top wall portion 16. Thesealing liner 22 cooperates with the associated container 14 to form aso-called “top/inside” seal (sometimes referred to as a top/cornerseal), that is, the sealing liner 22 engages the generally upwardly andinwardly facing surfaces of the finish of the container 14 (see FIG. 6).Notably, the type of sealing arrangement may be configured to have aso-called “seal length” which maintains the seal between the closure 12and the container 14 until the tamper-evident feature of the package, aswill be described below, fractures. Thus, the sealed condition of thecontainer is maintained until and after tamper-evidence is provided,further acting to preclude undetected tampering.

In a current embodiment, sealing liner 22 has been configured to provide0.020 inches of sealing compression, with the tamper-indicatingarrangement of the present package configured to providetamper-indication, by virtue of the corresponding thread pitch, of themulti-start thread formation, attendant to less than about 5° ofrelative rotation of the closure 12 and the container 14.

To provide the desired tamper-indication for the package 10, closure 12includes a tamper band 26 at least partially detachably connected to theskirt portion 18 of the closure. The tamper band 26 includes an annularband portion 28, and a plurality of circumferentially spaced, inwardlyextending tab-like flexible projections 30. Each projection 30 is joinedto band portion 28 by a respective, relatively thin hinge portion (seeFIG. 6) which promotes ease of application of the closure to theassociated container, while still affording the desiredsurface-to-surface contact for locking, interfering engagement betweenthe projections and the locking teeth (as will be described) on thecontainer 12.

The desired detachable connection of the pilfer band 26 to the closureskirt 18 is provided by way of a frangible connection therebetween,illustrated in phantom line at 32. Frangible connection 32 can be formedduring molding of the closure, or can alternatively be formed bycontinuous or discontinuous scoring of the closure, as is known in theart. In a current embodiment, it is contemplated that the tamper band 26completely separate from the skirt portion 18 during closure removal,with the tamper band remaining in place on the associated container 12.However, it is within the purview of the present invention that thetamper band may be configured for partial detachment from the skirtportion 18, such as by the provision of a relatively strong connectorportion between the tamper band 26 and the skirt portion 18.

With particular reference to FIGS. 3 and 5, therein is illustrated thecontainer 14 of the present tamper-evident package. The container 14includes a neck portion defining an opening, with the closure 12 beingconfigured for fitment to the neck portion for closing the openingdefined thereby. In order to permit rapid application and removal of theclosure, the neck portion of the container 14 includes an externalthread formation thereon, with the thread formation on the containerconfigured for mating engagement with the internal thread formation ofthe closure 12. To this end, the thread formation of the containerincludes a plurality of helical thread elements 40 for respectivecooperative engagement with the thread element 20 of the closure 12. Inthe illustrated embodiment, two of the cooperating thread elements areprovided on the closure of the container. However, the present packagemay be configured with a single helical thread element. The presentpackage may alternatively be provided with cooperating lug-type threadelements on the container 12 and closure 14.

In accordance with the present invention, the container 14 includes aplurality of circumferentially spaced locking teeth 42 provided on theneck portion of the container. The locking teeth 42 are configured tocooperate with the projections 30 on the closure 12 during closureremoval by interferingly engaging the projections. By this cooperativeengagement, the frangible connection 32 between the tamper-band 26 andthe skirt portion 18 of the closure 12 is fractured, thus providingclear visual evidence that the package has been opened.

As illustrated, the neck portion of the container 14 includes an annularshoulder 44 positioned generally above the locking teeth, and below theexternal thread elements on the container. Locking teeth 42 are at leastpartially positioned beneath shoulder 44, but it is desired that theratchet teeth 42 be of sufficient size to provide the desired lockingengagement with flexible projections 30. In the illustrated embodiment,the locking teeth 42 define a circle having a diameter substantiallyequal to the diameter of shoulder 44, but the teeth may be enlarged toprovide enhanced engagement with projections 30.

The shoulder 44 desirably acts to confine the projections 30 of theclosure tamper band in a position for the desired interfering engagementwith the locking teeth 42. Additionally, the outwardly taperingconfiguration of the upper annular shoulder 44 desirably acts to guideand upwardly flex the projections 30 during closure application. Duringclosure application, the projections 30 are in a generally horizontaldisposition, as illustrated in phantom line in FIG. 6. After closureapplication, the projections 30 extend generally upwardly and inwardlyfor engagement with the locking teeth 44, as further illustrated in FIG.6.

Handling of the container of the preset package by automated packagingequipment is facilitated by the provision of support ring 44 positionedon the neck portion of the container generally beneath the locking teeth42.

In accordance with the preferred form, each of the locking teeth 42includes a generally radially and vertically oriented locking surfacepositioned for engagement with a respective one of the projections 30 ofthe closure 12. Each of the locking teeth further includes a ramp-likeoutwardly tapering guide surface which extends generally outwardly fromthe neck portion of the container, generally opposite the lockingsurface 48. The guide surface is oriented such that during rotationalapplication of the closure to the container (by right-hand rotation inaccordance with the illustrated embodiment), the projections 30 of theclosure tamper band are guided by the guide surfaces and urged generallyoutwardly over the locking teeth. As each of the projections passes oneor more of the locking teeth, the resilience of the projections acts toreturn the projections to a generally inwardly, upwardly extendingorientation.

As illustrated in FIG. 5, it will be observed that the locking teeth 42are unevenly circumferentially spaced about the neck portion of thecontainer 14, with the spacing between the teeth corresponding to thespacing between projections 30, or multiples thereof. This assuressubstantially simultaneous engagement of a plurality of the projections30 with a like plurality of the locking teeth during closure removal.FIG. 5 illustrates a mold parting line defined by the neck portion ofthe container 14, which corresponds to the line or plane along which themold for the neck portion opens. As illustrated, the closure 14 includesa pair of locking teeth 42 having their respective locking surfacesaligned with the parting line.

As will be observed, the locking teeth 42 are arranged in first andsecond diametrically opposed groups on the neck portion of thecontainer, with the locking teeth 42 of each group being evenlycircumferentially spaced.

In a current embodiment, the locking teeth 42 of each of the first andsecond groups are circumferentially spaced apart at 30° intervals, asillustrated in FIG. 5.

As noted above, the tamper-evident package of the present invention hasbeen particularly configured to promote very rapid tamper-indicationattendant to removal of closure 12 from container 14. To this end, theflexible projections 30 of the pilfer band 26 of closure 12 arepositioned in predetermined circumferential relationship with respect tothe internal thread formation, including thread elements 20, of theclosure. This is achieved during closure molding by fixing the relativeposition of the mold which forms the projections 30 (sometimes referredto as the tab sleeve) relative to the portion of the mold which formsthe thread elements 20 (sometimes referred to as the core pin).

By virtue of this predetermined relationship, the position of theflexible projections 30 relative to locking teeth 42, after the closureis fully applied to the container, can be very precisely predetermined.In view of this, the present invention contemplates that thecircumferential spacing “c” between adjacent ones of the flexibleprojections 30 (FIG. 4), is at least as great as the circumferentialdimension of each of the locking teeth 42, that is, the spacing betweenadjacent ones of the flexible projections 30 is sufficiently great as topermit one of the locking teeth 42 to be received between adjacent onesof the projections 30. On balance, the spacing between the projections30 is preferably selected to closely correspond to the spacing betweenthe ratchet teeth 42 of each of the first and second groups of ratchetteeth to thereby position a plurality of the projections 30 for lockingengagement with a respective plurality of the ratchet teeth 42 toprovide a high level of resistance to relative rotation to therebyassure tamper band fracture.

By this arrangement, the flexible projections 30 and the locking teeth42 can be fitted in very closely spaced cooperating engagement when theclosure 12 is fully applied to the container 14. To further facilitatesuch closely spaced fitting, while still maximizing the dimension of theprojections 30 for the desired degree of rigidity, each of the flexibleprojections 30 is preferably inwardly tapering. As shown in FIG. 4, in acurrent embodiment, each of the projections 30 at its relatively thinhinge portion has a dimension “b”, which is greater than a dimension “a”at an inner edge portion of each projection 30. In a current embodiment,dimension “a” is 0.180 inches, while dimension “b” is 0.200 inches.

By virtue of the closely-spaced relationship of the flexible projections30 and locking teeth 42 after the closure is fully applied to thecontainer, the frangible connection of the closure is broken before nomore than about 5°, or less, of rotation of the closure relative to thecontainer during removal fo the closure. By virtue of this desirablyfast-acting tamper-indication function, fracture of the closure is verydesirably effected prior to unsealing of the container by disengagementof sealing liner 22 from the container finish. Highly effectiveresistance to tampering is thus provided.

From the foregoing, it will be observed that numerous modifications andvariations can be effected without departing from the true spirit andscope of the novel concept of the present invention. It is to beunderstood that no limitation with respect to the specific embodimentillustrated herein is intended or should be inferred. The disclosure isintended to cover by the appended claims all such modifications as fallwithin the scope of the claims.

1. A tamper-evident package, comprising: a container having a neckportion defining an opening, said container having an external threadformation on said neck portion, said thread formation including at leastone helical thread element, said container further including a pluralityof circumferentially spaced locking teeth positioned on said neckportion beneath said thread formation, and a closure configured forfitment to the neck portion of said container for closing said opening,said closure including a top wall portion and a depending annular skirtportion having an internal thread formation for mating engagement withthe external thread formation on said neck portion of said container,said closure including a tamper band depending from and at leastpartially detachably connected to said skirt portion by a frangibleconnection, said tamper band including an annular band portion, and aplurality of inwardly extending flexible projections each movable abouta respective horizontal hinge portion joined to said annular bandportion, at least one of said projections being engageable with at leastone of said locking teeth on said container during removal of saidclosure from said container for fracturing said frangible connection toprovide visual evidence of opening of said package, said locking teethbeing unevenly circumferentially spaced about the neck portion of saidcontainer, with said flexible projections being spaced apart by adistance at least as great as the circumferential dimension of each ofsaid locking teeth.
 2. A tamper-evident package in accordance with claim1, wherein: said flexible projections of said tamper band are positionedin predetermined circumferential relationship with respect to saidinternal thread formation.
 3. A tamper-evident package in accordancewith claim 1, wherein: said locking teeth include first and secondgroups of said locking teeth positioned in diametrically opposedrelationship.
 4. A tamper-evident package in accordance with claim 3,wherein: the locking teeth of each of said first and second groups areevenly circumferentially spaced apart.
 5. A tamper-evident package inaccordance with claim 1, wherein: said container includes annularshoulder positioned adjacent to and above said locking teeth and beneathsaid external thread formation.
 6. A tamper-evident package inaccordance with claim 1, wherein: said flexible projections are inwardlytapering.
 7. A tamper-evident package in accordance with claim 1,wherein: each of said locking teeth includes a generally radiallyoriented locking surface for engagement by one of said projections ofsaid closure, and a generally outwardly tapering guide surface oppositesaid locking surface extending from said neck portion to said lockingsurface.
 8. A tamper-evident package in accordance with claim 1,wherein: the spacing between said locking teeth corresponds to thespacing between said projections, or multiples thereof.
 9. Atamper-evident package in accordance with claim 1, wherein: said hingeportion of each of said projections of said closure is relatively thin.10. A tamper-evident package in accordance with claim 1, wherein: saidexternal thread formation includes a plurality of helical threadelements.
 11. A tamper-evident package, comprising: a container having aneck portion defining an opening, said container having an externalthread formation on said neck portion, said thread formation includingat least one helical thread element, said container further including aplurality of circumferentially spaced locking teeth positioned on saidneck portion beneath said thread formation, and a closure configured forfitment to the neck portion of said container for closing said opening,said closure including a top wall portion and a depending annular skirtportion having an internal thread formation for mating engagement withthe external thread formation on said neck portion of said container,said closure including a tamper band depending from and at leastpartially detachably connected to said skirt portion by a frangibleconnection, said tamper band including an annular band portion, and aplurality of inwardly extending flexible projections each movable abouta respective horizontal hinge portion joined to said annular bandportion, at least one of said projections being engageable with at leastone of said locking teeth on said container during removal of saidclosure from said container for fracturing said frangible connection toprovide visual evidence of opening of said package, said locking teethbeing unevenly circumferentially spaced about the neck portion,including first and second groups of locking teeth positioned indiametrically opposed relationship, with the locking teeth of each ofsaid first and second groups being evenly circumferentially spacedapart, said flexible projections of said tamper band being positioned inpredetermined circumferential relationship with respect to said internalthread formation, so that when said closure is applied to saidcontainer, one of said projections is positioned between each adjacentpair of said locking teeth of said first group and between each adjacentpair of said locking teeth of said second group.
 12. A tamper-evidentpackage in accordance with claim 11, wherein: when said closure isapplied to said container, each of said locking teeth is engageable by arespective one of said projections.
 13. A tamper-evident package inaccordance with claim 1 1, wherein: said frangible connection of saidclosure is broken during removal of said closure from said containerbefore said closure unseals said opening of said container.
 14. Atamper-evident package in accordance with claim 13, wherein: saidfrangible connection is broken before no more than about 5 degrees ofrotation of said closure relative to said container during removal ofsaid closure.
 15. A tamper-evident package in accordance with claim 11,wherein: said flexible projections are spaced apart by a distance atleast as great as the circumferential dimension of each of said lockingteeth.
 16. A tamper-evident package in accordance with claim 11,wherein: said container includes an annular shoulder positioned adjacentto and above said locking teeth and beneath said external threadformation.
 17. A tamper-evident package in accordance with claim 11,wherein: said flexible projections are inwardly tapering.